scholarly journals A lex naturalis delineates components of a human-specific, adrenal androgen-dependent, p53-mediated ‘kill switch’ tumor suppression mechanism

2020 ◽  
Vol 27 (2) ◽  
pp. R51-R65
Author(s):  
Jonathan Wesley Nyce
Keyword(s):  
Body Size ◽  
Cancer Risk ◽  
Tumor Suppression ◽  
Adrenal Androgen ◽  
Lifetime Cancer Risk ◽  
Polycyclic Aromatic ◽  
Carcinogenic Substances ◽  
Suppression Mechanism ◽  
Species Specific ◽  
Human Specific

We have recently described in this journal our detection of an anthropoid primate-specific, adrenal androgen-dependent, p53-mediated, ‘kill switch’ tumor suppression mechanism that reached its fullest expression only in humans, as a result of human-specific exposure to polycyclic aromatic hydrocarbons caused by the harnessing of fire – but which has components reaching all the way back to the origin of the primate lineage. We proposed that species-specific mechanisms of tumor suppression are a generalized requirement for vertebrate species to increase in body size or lifespan beyond those of species basal to their lineage or to exploit environmental niches which increase exposure to carcinogenic substances. Using empirical dynamic modeling, we have also reported our detection of a relationship between body size, lifespan, and species-specific mechanism of tumor suppression (and here add carcinogen exposure), such that a change in any one of these variables requires an equilibrating change in one or more of the others in order to maintain lifetime cancer risk at a value of about 4%, as observed in virtually all larger, longer-lived species under natural conditions. Here we show how this relationship, which we refer to as the lex naturalis of vertebrate speciation, elucidates the evolutionary steps underlying an adrenal androgen-dependent, human-specific ‘kill switch’ tumor suppression mechanism; and further, how it prescribes a solution to ‘normalize’ lifetime cancer risk in our species from its current aberrant 40% to the 4% that characterized primitive humans. We further argue that this prescription writ by the lex naturalis represents the only tenable strategy for meaningful suppression of the accelerating impact of cancer upon our species.

scholarly journals Exposure to Particulate PAHs on Potential Genotoxicity and Cancer Risk among School Children Living Near the Petrochemical Industry

2021 ◽  
Vol 18 (5) ◽  
pp. 2575
Author(s):  
Nor Ashikin Sopian ◽  
Juliana Jalaludin ◽  
Suhaili Abu Bakar ◽  
Titi Rahmawati Hamedon ◽  
Mohd Talib Latif
Keyword(s):  
Cancer Risk ◽  
Environmental Protection Agency ◽  
Primary Schools ◽  
Petrochemical Industry ◽  
Industrial Area ◽  
Industrial Emissions ◽  
Buccal Cells ◽  
Genotoxic Effects ◽  
Lifetime Cancer Risk ◽  
Polycyclic Aromatic

This study aimed to assess the association of exposure to particle-bound (PM2.5) polycyclic aromatic hydrocarbons (PAHs) with potential genotoxicity and cancer risk among children living near the petrochemical industry and comparative populations in Malaysia. PM2.5 samples were collected using a low-volume sampler for 24 h at three primary schools located within 5 km of the industrial area and three comparative schools more than 20 km away from any industrial activity. A gas chromatography–mass spectrometer was used to determine the analysis of 16 United States Environmental Protection Agency (USEPA) priority PAHs. A total of 205 children were randomly selected to assess the DNA damage in buccal cells, employing the comet assay. Total PAHs measured in exposed and comparative schools varied, respectively, from 61.60 to 64.64 ng m−3 and from 5.93 to 35.06 ng m−3. The PAH emission in exposed schools was contributed mainly by traffic and industrial emissions, dependent on the source apportionment. The 95th percentiles of the incremental lifetime cancer risk estimated using Monte Carlo simulation revealed that the inhalation risk for the exposed children and comparative populations was 2.22 × 10−6 and 2.95 × 10−7, respectively. The degree of DNA injury was substantially more severe among the exposed children relative to the comparative community. This study reveals that higher exposure to PAHs increases the risk of genotoxic effects and cancer among children.

scholarly journals Classroom Dust-Bound Polycyclic Aromatic Hydrocarbons in Jeddah Primary Schools, Saudi Arabia: Level, Characteristics and Health Risk Assessment

2020 ◽  
Vol 17 (8) ◽  
pp. 2779
Author(s):  
Mansour A. Alghamdi ◽  
Salwa K. Hassan ◽  
Noura A. Alzahrani ◽  
Marwan Y. Al Sharif ◽  
Mamdouh I. Khoder
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Cancer Risk ◽  
Urban Schools ◽  
Health Risks ◽  
Aromatic Hydrocarbons ◽  
Primary Schools ◽  
Residential Schools ◽  
Suburban Schools ◽  
Lifetime Cancer Risk ◽  
Polycyclic Aromatic

Data concerning polycyclic aromatic hydrocarbons (PAHs) in Jeddah’s schools, Saudi Arabia, and their implications for health risks to children, is scarce. Classroom air conditioner filter dusts were collected from primary schools in urban, suburban and residential areas of Jeddah. This study aimed to assess the characteristics of classroom-dust-bound PAHs and the health risks to children of PAH exposure. Average PAH concentrations were higher in urban schools than suburban and residential schools. Benzo (b)fluoranthene (BbF), benzo(ghi)perylene (BGP), chrysene (CRY) and Dibenz[a,h]anthracene (DBA) at urban and suburban schools and BbF, BGP, fluoranthene (FLT) and indeno (1, 2, 3, −cd)pyrene (IND) at residential schools were the dominant compounds in classroom dust. PAHs with five aromatic rings were the most abundant at all schools. The relative contribution of the individual PAH compounds to total PAH concentrations in the classroom dusts of schools indicate that the study areas do share a common source, vehicle emissions. Based on diagnostic ratios of PAHs, they are emitted from local pyrogenic sources, and traffic is the significant PAH source, with more significant contributions from gasoline-fueled than from diesel cars. Based on benzo[a]pyrene equivalent (BaPequi) calculations, total carcinogenic activity (TCA) for total PAHs represent 21.59% (urban schools), 20.99% (suburban schools), and 18.88% (residential schools) of total PAH concentrations. DBA and BaP were the most dominant compounds contributing to the TCA, suggesting the importance of BaP and DBA as surrogate compounds for PAHs in this schools. Based on incremental lifetime cancer risk (ILCingestion, ILCRinhalation, ILCRdermal) and total lifetime cancer risk (TLCR)) calculations, the order of cancer risk was: urban schools > suburban schools > residential schools. Both ingestion and dermal contact are major contributors to cancer risk. Among PAHs, DBA, BaP, BbF, benzo(a)anthracene (BaA), benzo(k)fluoranthene (BkF), and IND have the highest ILCR values at all schools. LCR and TLCR values at all schools were lower than 10−6, indicating virtual safety. DBA, BaP and BbF were the predominant contributors to cancer effects in all schools.

scholarly journals Occurrence and Ecological and Human Health Risk Assessment of Polycyclic Aromatic Hydrocarbons in Soils from Wuhan, Central China

2018 ◽  
Vol 15 (12) ◽  
pp. 2751 ◽  
Author(s):  
Tekleweini Gereslassie ◽  
Ababo Workineh ◽  
Xiaoning Liu ◽  
Xue Yan ◽  
Jun Wang
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Cancer Risk ◽  
Aromatic Hydrocarbons ◽  
Solid Phase ◽  
Human Health Risk ◽  
Environmental Pollutants ◽  
Soil Samples ◽  
Central China ◽  
Lifetime Cancer Risk ◽  
Polycyclic Aromatic

Polycyclic aromatic hydrocarbons are large groups of ubiquitous environmental pollutants composed of two or more fused aromatic rings. This study was designed to evaluate the distribution, potential sources, and ecological and cancer risks of eleven polycyclic aromatic hydrocarbons from Huangpi soils in Wuhan, central China. The soil samples for this study were taken from 0–10 cm and 10–20 cm soil depths. A modified matrix solid-phase dispersion extraction method was applied to extract analytes from the soil samples. A gas chromatograph equipped with a flame ionization detector was used to determine the concentrations of the compounds. The sum mean concentrations of the polycyclic aromatic hydrocarbons were 138.93 and 154.99 µg kg−1 in the 0–10 cm and 10–20 cm soil depths, respectively. Benzo[a]pyrene and fluorene were the most abundant compounds in the 0–10 cm and 10–20 cm soil depths, respectively. The quantitative values of the pyrogenic index, total index, and diagnostic ratio used in this study showed that the polycyclic aromatic hydrocarbons have a pyrogenic origin. The negligible and maximum permissible concentrations values for naphthalene, acenaphthylene, acenaphthene, phenanthrene, anthracene, pyrene, benz[a]anthracene, and benzo[a]pyrene indicated a moderate ecological risk. The incremental lifetime cancer risk values for adults and children showed a low and moderate cancer risk, respectively.

scholarly journals Human Health Assessment of Sixteen Priority Polycyclic Aromatic Hydrocarbons in Contaminated Soils of Northwestern Algeria

2021 ◽  
Vol 11 (31) ◽  
Author(s):  
Ahmed Halfadji ◽  
Mohamed Naous ◽  
Farida Bettiche ◽  
Abdelkrim Touabet
Keyword(s):  
Cancer Risk ◽  
Aromatic Hydrocarbons ◽  
Contaminated Soils ◽  
Carcinogenic Risk ◽  
Risk Assessments ◽  
Lifetime Cancer Risk ◽  
Exposure Pathways ◽  
Polycyclic Aromatic ◽  
Adults And Children ◽  
Incremental Lifetime Cancer Risk

Background. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental organic contaminants generated by incomplete combustion of organic materials that are widely distributed in soils. Objectives. This study represents the first attempt to examine the health toxicity of 16 detected PAHs in contaminated soil, via different exposure pathways to populations in northwestern Algeria. Methods. The toxicity equivalency quotients (TEQ) of PAHs were evaluated. The carcinogenic risk assessment of incremental lifetime cancer risk (ILCR) from ingestion, inhalation, and dermal exposure pathways to each PAH in soil are described. Results. Incremental lifetime cancer risk values were in the upper limit of the tolerable range (10−6–10−4) for adults and children. The total cancer risk of PAH-contaminated soils for children, adolescents and adults was 2.48×10−5, 2.04×10−5 and 3.12×10−5mg.kg−1d−1, respectively. The highest potential cancer risks were identified for adults and children, with adolescents having the lowest risks. Across exposure pathways, the dermal contact and ingestion pathways had the greatest contributions to the carcinogenic risk of human exposure to PAHs. Conclusions. Further research and guidelines are needed for risk assessments of PAHs in agricultural, residential/urban, and industrial areas, and further risk assessments should include risks posed by exposure through air. Competing Interests. The authors declare no competing financial interests.

scholarly journals HUMAN HEALTH HAZARD OF POLYCYCLIC AROMATIC HYDROCARBON IN ROAD DUST IN HA NOI METROPOLIS

2018 ◽  
Vol 54 (2A) ◽  
pp. 27
Author(s):  
Vo Thi Le Ha
Keyword(s):  
Cancer Risk ◽  
Health Hazard ◽  
Road Dust ◽  
Gas Chromatography Mass Spectrometry ◽  
Lifetime Cancer Risk ◽  
Total Cancer ◽  
Polycyclic Aromatic ◽  
The Mean ◽  
Potential Cancer ◽  
Human Health Hazard

This study investigates PAHs content in road dust of Hanoi metropolis, Vietnam. The samples were colected from the roads around city and analyzed by gas chromatography mass spectrometry (GC/MS). The total PAHs mass concentration ranges from 33.88 μg/kg to 5588,16 μg/kg, with the mean of 356,24 μg/kg in which HMW accounted up 70 % and LMW made up 30 %. The toxic equivalence factors (TEFs), mutagenic potency equivalent factors (MEFs) and the incremental lifetime cancer risk (ILCR) methodologies were applied to evaluate human exposure to carcinogenic PAHs sources. Carcinogenic equivalents (BaP-TEQ) and mutagenic equivalents (BaP-MEQ) were calculated from the potency relative to BaP (TEF) and BaP (MEF). The value of BaP-TEQ for 8 PAHs varied from 1.13 μg/kg to 195.23 μg/kg with mean of 24.34 μg/kg, while the value of BaP-MEQ ranged 1.45 μg/kg to 123.15 μg/kg with mean of 19.96 μg/kg. Basing on ILCRs model, the total cancer risk for children and adults was up to 1.6×10-5 and 3.9×10-5, posing a moderate potential cancer risk, respectively.

scholarly journals Polycyclic Aromatic Hydrocarbons in Costal Sediments and Indian Halibuts of Asaluyeh, Kangan, Khark, Emam Hasan and Bushehr Coasts, Iran: Distribution Pattern and Health Risk Assessment

2021 ◽  
Author(s):  
Ghafour Nourian ◽  
Neamat Haghighi ◽  
Tayebeh Tabatabaei ◽  
Esmaeil Kohgardi ◽  
Abdul Pazira
Keyword(s):  
Risk Assessment ◽  
Polycyclic Aromatic Hydrocarbons ◽  
Cancer Risk ◽  
Health Risk ◽  
Health Risk Assessment ◽  
Aromatic Hydrocarbons ◽  
Lifetime Cancer Risk ◽  
Ring Compounds ◽  
Excess Cancer Risk ◽  
Polycyclic Aromatic

Abstract A total 20 sediment and 20 Indian halibut samples were sampled from Asaluyeh, Kangan, Khark, Emam Hasan and Bushehr coast, Bushehr province, Iran for studying distribution and health risk assessment of polycyclic aromatic hydrocarbons (PAHs). PAHs were analyzed using HPLC. The mean ƩPAHs concentrations in sediment and Indian halibut samples were 6.894 ± 1.4301 and 14.807 ± 7.486 mg/kg, respectively. There was a significant positive relationship (P < 0.05) between ƩPAHs, 2–3 ring compounds, and 4 ring compounds in the sediments and Indian halibut samples. ƩPAHs concentration in sediments and Indian halibuts was higher in Asaluyeh area followed by Khark area. The values of PAHs pollution in the Bushehr province coastline were low to very high. The toxic equivalent quotient (TEQ), excess cancer risk (ECR), and the incremental lifetime cancer risk (ILCR) were applied for health risk assessment. Based on TEQ calculation, DA was a good marker in assessing PAHs related to health risk. DDI values for ∑PAHs and ∑CPAHs (carcinogenic PAHs) were also highest in Asaluyeh and Kangan, respectively. ILCR values for sediments in 10% of all stations and cumulative ECR values for Indian halibuts in all studied areas exceeded the USEPA acceptable level thus suggesting a potential cancer risk. Thus, regular monitoring of PAHs pollutants in the coastlines of Bushehr province is recommended.

Sign in / Sign up

Export Citation Format

Share Document